XFX XTR Series 850W PSU Review

XFX cooperates closely with Seasonic for its PSU products. That's a major advantage, since Seasonic is a top OEM. The XTR line is XFX's second-best, after the XTS family, and today's review focuses on the 850W model.

XFX is a division of PINE Technology Holdings Limited and its main product categories are graphics cards and PSUs. Currently, the company has six active PSU lines with the XTS family up front and the XTR series behind it. The XTRs cover almost every market segment with capacities between 500W and 1250W. All XFX PSUs are made by Seasonic, so we expect high performance out of them. Today, we're looking at the P1-850B-BEFX specifically.

You may find this PSU selling under the Pro Series Gold name since XFX recently made some changes to the way it markets power supplies. Since the same company also has a Pro Series family that includes several Bronze members, it decided to add all previous Pro Gold models to the XTR family for simplicity's sake. Unfortunately, some vendors still show pictures of the old box with the previous name, even though they're actually selling the newer XTR. 

The XTR 850W features modular cabling, and its external design helps it stand out from the crowd. This PSU is based on Seasonic's former high-end platform (KM3), so its performance should be exceptional. On top of that, since it isn't a new product, you should be able to find it priced aggressively. Occasional rebates even bring the XTR 850W down under $100. Of course, that's a good price for a fully modular 850W 80 PLUS Gold-rated PSU sporting only Japanese capacitors and a Fluid Dynamic Bearing fan. Seasonic's power supplies aren't known for low prices, so it's interesting that XFX is able to make this model so affordable. We're not complaining; rather, we'd like to see XFX drop its price even more if possible.

So far, the only issue we have with the XTR 850W is its 120mm fan, which has to spin faster in order to move the same volume of air as the competition's 140mm fans. This translates into higher noise levels.


The PSU is 80 PLUS Gold-certified and, according to its manufacturer, it is able to deliver full power continuously at up to 50 degrees Celsius ambient temperatures. According to our experience with Seasonic's KM3 platform, this is indeed the case. Moreover, the DC-DC converters responsible for generating the minor rails ensure compatibility with the C6 and C7 sleep states that Intel's Haswell processors introduced.

Besides modular cables, you also get a full set of protection features. Only over-current protection is missing, since it is meaningless in a high-capacity single +12V rail unit. The cooling fan uses a Fluid Dynamic Bearing that facilitates a longer lifetime.

Meanwhile, as mentioned, the only downside appears to be the smaller fan. A larger one would enable the same airflow at lower speeds, hence noise output would be lower. At least we get a semi-passive mode to keep acoustics in check under light loads. Physically, the unit's dimensions are small given its capacity, and the provided five-year warranty is satisfactory. 

Power Specifications

Max. PowerAmps25257030.5
Total Max. Power (W)850

The minor rails are quite strong, offering 125W maximum combined power. The single +12V rail is also powerful, and with up to 70A of current available, it easily supports multiple graphics cards. Finally, the 5VSB rail tops out at 15W of capacity, so it won't trouble you unless you want to charge two energy-hungry tablets at the same time.

Cables And Connectors

Modular Cables
DescriptionCable CountConnector Count (Total)
ATX connector 20+4 pin (610mm)1 1
Eight-pin EPS12V (655mm)1 1
4+4 pin EPS12V (655mm)11
6+2 pin PCIe (550mm+100)4 8
SATA (400mm+120mm+120mm+120mm)2 8
SATA (500mm+120mm)2 4
Four-pin Molex (400mm+100mm+100mm+100mm) / FDD (+100mm)1 4 / 1
Four-pin Molex (310mm+125mm)1 2

The number of cables is huge, even for a 850W PSU. A couple of EPS connectors, along with eight PCIe ones, are available simultaneously. You get a ton of SATA and peripheral connectors as well. The only flaw is that the single Berg connector is fixed on a modular cable along with several four-pin Molex connectors. Normally, the FDD connector works best as an adapter since only a few folks need it. Finally, all connectors employ standard 18-gauge wires.

Power Distribution

Since this PSU features a single +12V rail, we do not have anything to say about its power distribution.

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